I tried using batteries for awhile instead of the Mobee charger and it happened less, so I bought a new Mobee battery pack, mine was very old. But it is still happening. It is 100% charged. Do I need a bluetooth booster or something?

A range extender?

(Sorry...couldn't resist.)

Nyuk, nyuk, nyuk. Wise guy.

Why I oughtta...!

That is a known intermittent issue with Magic Mouse and Magic Trackpad in Mavericks and it is still present in the Yosemite beta. It has been reported to Apple and they are well aware of the problem although it has not yet been fixed (or even why it is happening apparently). Power the mouse or trackpad off and wait for the message that it has been disconnected then power the device back on and voila the cursor reappears. FWIW I am finding it occurring more often in Yosemite than I did in Mavericks. I have found one or two apps in Yosemite where it will reliably occur.

Hopefully this will be corrected before the Yosemite release. It is not a stopper but it sure as heck is annoying.

I'm still using Snowy. It is really, really annoying.

Have you tried the MM with another Mac to see what happens?

If you have an old corded USB mouse lying around, plug that in, just to keep the cursor available; you don't need to use it. This way you may never see the cursor disappear from the wireless mouse or trackpad.

I say this based on my set-up. I use a mouse on my opposite hand and a trackpad on my dominant and I have never noticed the cursor disappear "in all the years" I have been using Maverick.

I sure hope that last statement doesn't come back to bite me!

No worries, Ira.

If you just keep a USB mouse connected that solves it? Weird but worth a try. When I showed up with it at the Apple store during all the weird problems stuff, I didn't bring the MM because I thought this problem was related. From the reaction, they had only seen a wired mouse in old Apple commercials.

I can't believe this works. The wired mouse lights up now and then (paranormal activity) but the Magic Mouse has stopped disconnecting!

Add to that Mac OS X Lion (10.7.5).
I've had intermittent "Connection Lost" issues, but in the past 4 hours (after installing recharged batteries yesterday) it's recurred with extremely annoying frequency (starting with access to Macworld.com's "Safe from Shellshock" website – although I imagine that's merely coincidence).
In the interim I've run Disk Utility and restarted the iMac (mid-2011 2.5GHz Intel Core i5). So far, so good.